I used a random number generator to pick the winner from the 22 commenters. The winner was number 4 and that is P. Welch. Here's what he/she had to say:
Now if you want to claim your prize please contact me either through the contact form on the side bar or through regular e-mail at c.m.j.winkelman[at]home.nl with your snail mail address so I can have the book sent to you. Please do so within two weeks. If I don't hear from you before May 2, I will pick another winner from the original commenters. Comments for my giveaway post will be closed for that reason. But I'm sure you would like to claim your prize so a second draw won't be necessary. ;-)
As for the rest of you, thank you so much for participating and for your kind birthday wishes. Hopefully next time it will be your turn to win, be it on this blog or another.
For now I wish you all a wonderful and artsy day!